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Porcelain is a ceramic material made by heating raw materials, generally including clay in the form of kaolin, in a kiln to temperatures between 1,200 �C (2,192 �F) and 1,400 �C (2,552 �F). The toughness, strength, and translucence of porcelain arise mainly from the formation of glass and the mineral mullite within the fired body at these high temperatures.

Porcelain derives its present name from old Italian porcelain (cowrie shell) because of its resemblance to the translucent surface of the shell. Porcelain can informally be referred to as "china" in some English-speaking countries, as China was the birth place of porcelain making. Properties associated with porcelain include low permeability and elasticity; considerable strength, hardness, glassiness, brittleness, whiteness, translucence, and resonance; and a high resistance to chemical attack and thermal shock.

For the purposes of trade, the Combined Nomenclature of the European Communities defines porcelain as being "completely vitrified, hard, impermeable (even before glazing), white or artificially coloured, translucent (except when of considerable thickness) and resonant." However, the term porcelain lacks a universal definition and has "been applied in a very unsystematic fashion to substances of diverse kinds which have only certain surface-qualities in common" (Burton 1906).

Porcelain is used to make table, kitchen, sanitary, and decorative wares; objects of fine art; and tiles. Its high resistance to the passage of electricity makes porcelain an excellent insulator. Dental porcelain is used to make false teeth, caps, crowns and veneers.

Porcelain tiles

Porcelain tiles are ceramic tiles with a water absorption rate of less than 0.5 percent that are used to cover floors and walls. They can either be unglazed or glazed.

The hardness of the tile is rated from zero to five according to the ASTM C1027 (or ISO 10545-7) test for surface abrasion resistance of glazed tile. This rating, (sometimes mistakenly called the PEI rating) determines the tiles suitability for various end use conditions. Generally, very hard tiles are used in homes, while the softer tiles are easier to mill and are mostly used as insulators for low grade electronics.

Large scale production of porcelain tile is undertaken in many countries, including the United States, China, Italy, Bulgaria, Turkey and Spain.